Industrial hammer



Oct. 12, 1965 c. o. GLASGOW 3,211,198

INDUSTRIAL HAMMER Filed April 6, 1964 INVENTOR. CLARENCE 0o Gmsaow United States Patent C) 3,211,198 INDUSTRIAL HAMMER Clarence 0. Glasgow, 2621) S. Yorktown, Tulsa, Okla. Filed Apr. 6, 1964, Ser. No. 357,693 2 Claims. (Cl. 145-29) This application is a continuation-in-part of my cpending application, Serial No. 172,641, now Patent No. 3,186,456, filed February 12, 1962, for Industrial Hammer.

This invention relates generally to improved industrial hammers. More particularly, but not by way of limitation, this invention relates to an improved industrial hammer that is provided with replaceable impact members.

Hammers having replaceable impact members satisfy requirements for many different hammer types by providing a hammer that, by the expedient of interchanging impact members or faces, can be used for many purposes. Also, many industries require extensive use of nonmetallic impact members. As might be expected, impact members formed of non-metallic materials rapidly become worn or destroyed in use. When service conditions require continuous use of non-metallic impact members, it is almost essential that the members be of the replaceable type.

In either circumstance, i.e., whether various types of hammers are required, or whether non-metallic impact members must be used, the prime concern of industries is to reduce the cost of their particular products to meet competition. Obviously two factors influencing the cost of a manufactured product are the cost of the tools used in constructing the product and the cost of the labor. Replaceable impact member hammers reduce the number of hammers that must be purchased and maintained, and also reduce the replacement cost or non-metallic hammers.

Replaceable impact member hammers, per se, are not new. They have been used for many years and many different types have been constructed. For the most part, hammers of this type have not been satisfactory because the impact members have loosened during use. In hammers in which the impact members have remained tight for any extended period of use, the hammers have been those requiring the greatest time to replace the impact members and were generally the most complex and expensive.

Non-metallic impact members have generally been constructed from either rawhide, synthetic resins, or rubber. Rawhide and synthetic resin, while providing a relatively non-marring impact face, have the disadvantage of lacking resiliency. Even though these materials are tough and last for a reasonable time, they are subject to deformation during use. Rubber, in the usual compositions, provides the advantage of resiliency and resistance to deformation, but will rebound in a dangerous fashion unless used with extreme care. Metallic impact members have been commonly constructed from lead or lead alloys, aluminum, steel, and brass or brass alloys.

This invention provides an improved hammer having replaceable impact members. In general, a hammer constructed in accordance with the invention includes a chuck rigidly attached to an elongated handle. The chuck is provided with one or more threaded, tapered bores. Each impact face or member provided has a threaded, tapered shank which is screwed into the threaded bore of the chuck. Furthermore, the manner in which the chuck is rigidly attached to the handle is such that neither the chuck nor handle is weakened during severe usage, and yet the handle can be readily removed from the chuck when desired.

One object of the present invention is to provide an improved industrial hammer having replaceable impact members that will not loosen during use.

Another object of the invention is to provide an improved industrial hammer that has impact members which can be easily and quickly replaced.

A further object of the invention is to provide an improved industrial hammer than can be economically manufactured.

Still another object of the invention is to provide an improved industrial hammer having replaceable impact members, which impact members are secured in a chuck having an easily removable handle rigidly fixed thereto.

The foregoing and additional objects and advantages of the invention will become more apparent as the following detailed description is read in conjunction with the accompanying drawings wherein like reference characters denote like parts in all views, and wherein:

FIG. 1 is an elevational view, partly in cross-section, of a hammer constructed in accordance with the invention;

FIG. 2 is a cross-sectional view of a portion of the hammer of FIG. 1 taken along the line 2-2 of FIG. 1.

FIG. 3 is a cross-sectional view of a portion of the handle of the hammer of FIG. 1 taken along the line 3-3 of FIG. 1;

FIG. 4- is a cross-sectional view of another portion of the handle of the hammer of FIG. 1 taken along the line 44 of FIG. 1; and,

FIG. 5 is an elevation view illustrating a different form of replaceable impact member that can be utilized in the hammer of FIG. 1.

Referring now to the drawings, and to FIG. 1 in particular, shown therein is one embodiment of an industrial hammer constructed in accordance with the invention. The hammer is generally designated by the reference character 10. As illustrated, the hammer It includes a chuck 12 and a handle 14. The handle 14 is inserted into and retained in a bore 16 which extends through the chuck 12. The chuck 12 also includes a pair of threaded, tapered bores 18 and 20, which extend partially into the chuck 12 in a transverse direction with respect to the longitudinal axis of the handle 14. Replaceable impact faces or members 22 and 24 are located in the bores 18 and 20, respectively.

As shown more clearly in FIG. 2 the bore 16 has a counterbore 26 which provides an outwardly facing shoulder 28 and a counterbore 30 in the opposite end thereof which provides an outwardly facing shoulder 32.

The handle 14, which is preferably constructed from a tubular member 34, is flattened near the extreme end 36 so that it has a resulting cross-sectional shape as illustrated by FIGS. 3 and 4. Alternatively, thehandle 14 may be constructed from a solid material if desired. The extreme end portion 36 of the handle 14 is preferably provided with an enlarged, resilient gripping portion 38 which encircles the member 34. The end 40 of the handle 14 which is inserted into the counterbore 30 of the chuck 12 is illustrated as having a threaded insert 42 positioned therein. The end 40 of the handle 14 is arranged to provide a shoulder 44 which, when the handle.

14 is inserted into the counterbore 30, abuts the shoulder 32 formed in the chuck 12.

The handle 14 is secured rigidly in the chuck 12 by a fastener 46 which is inserted into the bore 16 and is threadedly engaged with the threaded insert 42 of the handle 14. The threaded fastener 46 is provided with an enlarged head 48 which forms a shoulder 50 thereon.

Upon insertion of the threaded fastener 46 into the bore.

16, the enlarged head 48 enters the counterbore 26 and the shoulder 50 thereon engages the shoulder 28 in the chuck 12. Rotation of the threaded fastener 46 pulls the handle 14 securely into the counterbore 30 and against the shoulder 32 so that the resulting arrangement is a rigid handle-and-chuck combination. It should be pointed out that, contrary to the general practice of extending the screw transversely through the handle and chuck and thereby weakening the handle, the aforedescribed arrangement provides for securely fastening the handle 14 in the chuck 12 without weakening the handle 14 in any manner.

As shown in FIG. 1, the removable impact member 22 has an enlarged impact end 52 and a tapered, threaded shank 54 projecting therefrom. The maximum diameter of the threaded shank 54 is slightly smaller than the diameter of the enlarged head 52, providing a shoulder 56 thereon. The shoulder 56 of the impact member 22 may engage a surface 58 on the chuck 12 surrounding the tapered bore 18 when the impact face 22 is threadedly secured in the chuck 12. The engagement of the surfaces 56 and 58 aids in absorbing a portion of the load imposed upon the impact member 22 when the hammer is in use. The impact member 24 is similarly provided with an enlarged impact end 60 and a threaded, tapered shank 62. The impact member 24 also includes a surface 64 which may engage a surface 66 surrounding the threaded bore 20 in the chuck 12, thereby absorbing a portion of the workload as the impact member 24 is used. In the preferred form of the hammer 10, lower ends 57 and 59 on the threaded shanks 54 and 62, respectively, engage bottoms 61 and 63 in the tapered bores 16 and 18, respectively, to absorb a portion of the shock load imposed on the impact members during use of the hammer 10.

The impact members 22 and 24 may be constructed from various types of material. For example, either or both may be constructed from such material as rubber, rawhide, brass, lead, or steel. If a non-metallic material is to be used, it has been found that constructing the impact member of butyl rubber provides an impact member that will have a great deal of resiliency and yet will not rebound in a dangerous manner due to its characteristic of absorbing the force of impact. One disadvantage in the use of butyl rubber for the impact members has been found to be that it will be lacerated upon contact with relatively sharp edges. To counteract this disadvantage, it has been found highly desirable to mold into the butyl impact face a layer of flexible synthetic material, such as nylon. An impact member constructed in this manner will provide the many advantages of a member constructed completely from butyl rubber and yet will overcome the susceptibility of the butyl to become lacerated.

A hammer constructed in accordance with the invention is used in the same manner that any ordinary hammer is used. As previously pointed out, one of the big disadvantages of removable impact member type hammers constructed in the past has been the tendency of the impact members to become loosened in the hammer head or chuck during use. It has been found that the provision of the tapered bore 18 coacting with the mating tapered shank 54 of the impact member 22 serves to distribute the impact force from the enlarged portion 52 of the impact member 22 evenly along the threads on the shank 54 and in the bore 18, rather than imposing the entire force on the first thread, as may be the case if a straight thread is used. Furthermore, the tendency of the impact forces to shear the threads from the shanks 54 and 62 is resisted by the engagement of the lower end 57 of the shank 54 with the bottom 61 of the counterbore 18 and the engagement of the end 59 of the shank 62 with the bottom 63 of the counterbore 20.

. FIG. is provided to illustrate an alternate form of impact member, which is generally designated by the reference character 70. The replaceable impact member 70 includes a spherical impact surface 72 and a threaded, tapered shank 74 which corresponds to the previously described shanks 54 and 62. An annular flange 76 encircles the impact member 70 between the spherical impact surface 72 and the shank 74 and provides a shoulder '78 which may engage the surface of the chuck 12 surrounding either the tapered bore 18 or 20 upon insertion of the impact member 70 into the chuck 12. Naturally, the impact members may take any suitable form required to perform the job in which the hammer is to be used.

It should be apparent from the foregoing detailed description that a hammer constructed in accordance with the invention may be easily and economically manufactured. Also, a hammer constructed in accordance with the invention provides an arrangement of replaceable impact members that may be quickly and easily exchanged or replaced. The provision of the threaded, tapered shank on the impact members in cooperation with the threaded, tapered bores in the chuck or head of the hammer results in a replaceable impact member hammer having impact members that will not loosen during use of the hammer.

It should be pointed out that the embodiments described herein are by way of example only, and that many changes and modifications thereto can be made without departing from the spirit of the invention or from the scope of the annexed claims.

What I claim is:

1. An industrial hammer comprising:

a chuck having a first bore extending therethrough and having counterbores at each end of, and in communication With, said first bore and forming therewith, a pair of spaced apart, oppositely disposed shoulders, said chuck further having a threaded bore therein extending substantially normal to said first bore, said threaded bore being tapered toward said first bore;

an elongated handle having a hollow end portion dimensioned to fit in one of said counterbores in abutting contact With one of said shoulders;

threaded insert means mounted in said hollow end portion of said handle;

an elongated retaining member in the bore in said chuck and having a threaded shank engaging said threaded insert means and further having an enlarged head portion countersunk in the other of said counterbores than that receiving said handle and bearing against the shoulder formed by said other counterbore whereby said chuck and handle are rigidly interconnected; and

a low rebound butyl rubber impact member having an enlarged striking portion and a smaller threaded, tapered shank portion engaging said threaded, tapered bore, said enlarged striking portion defining a shoulder with said shank portion and said shoulder abutting said chuck.

2. An industrial hammer comprising:

a chuck of substantially circular cross section, the cross sectional area of said chuck decreasing uniformly from the center of said chuck to each end thereof, said chuck having formed on each end thereof a threaded bore, each of said threaded bores tapering inwardly toward the central portion of said chuck said chuck further having formed therein at the central portion thereof, a bore extending substantially normal to the longitudinal axis of said chuck, and a first and second counterbore formed at opposite ends of said bore to form a pair of spaced apart, oppositely disposed, shoulders, the first of said counterbores having a substantially greater diameter than the second of said counterbores;

an elongated handle having a hollow end portion dimensioned to fit in said first counterbore in abutting contact with the shoulder associated therewith;

a cylindrical, centrally threaded insert mounted in said end portion of said handle and held therein by an inwardly crimped portion of said handle;

a threaded, elongated retaining member mounted in the 2,795,443 6/57 Gratzmuller 287-53 bore of said chuck and engaging said insert, said re- 2,844,550 7/59 Clay 145-36 taining member having an enlarged head in abutting 3,025,062 3/62 Duflin 145-61 X engagement with the shoulder associated with said 3,040,792 6/62 West et al 145-36 second counterbore whereby said chuck and handle 5 3,042,092 7/62 Ekstrom 145-36 are rigidly interconnected; and

a 10W rebound butyl rubber impact member having a OTHER REFERENCES substantially cylindrical enlarged striking portion and s ft f d Nupla Hammers including Dead a Small, threadedg tapered shank Portion engagmg Blow Hammers, New Plastic Corporation, 1955, Bulletin at least one of said threaded, tapered bores, sard 10 5 enlarged striking portion defining a shoulder with said shank portion and said shoulder abutting said WILLIAM FELDMAN, Pri ary Examiner. chuck' MILTON s. MEHR, Examiner.

References Cited by the Examiner UNITED STATES PATENTS 1,441,903 1/23 Balaziuk 7-8 X 2,202,863 6/40 Plon 306-30 

1. AN INDUSTRIAL HAMMER COMPRISING: A CHUCK HAVING A FIRST BORE EXTENDING THERETHROUGH AND HAVING COUNTERBORES AT EACH END OF, AND IN COMMUNICATION WITH, SAID FIRST BORE AND FORMING THEREWITH, A PAIR OF SPACED APART, OPPOSITELY DISPOSED SHOULDERS, SAID CHUCK FURTHER HAVING A THREADED BORE THEREIN EXTENDING SUBSTANTIALLY NORMAL TO SAID FIRST BORE, SAID THREADED BORE BEING TAPERED TOWARD SAID FIRST BORE; AN ELONGATED HANDLE HAVING A HOLLOW END PORTION DIMENSIONED TO FIT IN ONE OF SAID COUNTERBORES IN ABUTTING CONTACT WITH ONE OF SAID SHOULDERS; THREADED INSERT MEANS MOUNTED IN SAID HOLLOW END PORTION OF SAID HANDLE; AN ELONGATED RETAINING MEMBER IN THE BORE IN SAID CHUCK AND HAVING A THREADED SHANK ENGAGING SAID THREADED INSERT MEANS AND FURTHER HAVING AN ENLARGED HEAD PORTION COUNTERSUNK IN THE OTHER OF SAID COUNTERBORES THAN THAT RECEIVING SAID HANDLE AND BEARING AGAINST THE SHOULDER FORMED BY SAID OTHER COUNTERBORE WHEREBY SAID CHUCK AND HANDLE ARE RIGIDLY INTERCONNECTED; AND A LOW REBOUND BUTYL RUBBR IMPACT MEMBER HAVING NA ENLARGED STRIKING PORTION AND A SMALLER THREADED, TAPERED SHANK PORTION ENGAGING SAID THREADED, TAPERED BORE, SAID ENLARGED STRIKING PORTION DEFINIGN A SHOULDER WITH SAID SHANK PORTION AND SAID SHOULDER ABUTTING SAID CHUCK. 